I have setup an alternative to the modding wiki at http://s2howto.com/modding. It's not finished yet but it already has a good amount of content to get you started with scripting
-- Not sure if I ever do the UI modding stuff.

That forum is about the source engine mainly. I highly doubt they'd know anything about the K2 stuff. Besides...who knows about it anway? There are maybe a handful of people who can properly mod this game